Well, I guess there are two parts to this analysis...
The part where I'm a little disappointed in the drives performance and the other part where I eat crow...
Anyway, I got my Samsung in today and have been playing with it most of the night (for way, way too long).
I think we have enough info to put its suitability for unRAID to bed. Here is what I did. On my benchmark, I tested the HD204UI with an aligned partition (2048) and with an unaligned partition (63) for a 4k drive.
I ran HDTune and Crystal Disk Mark each time.
The HDTune results are almost identical whether aligned or unaligned. Either way it was 103.3 MB/sec average transfer.
However, CrystalDiskMark brought out the difference. Sequential read/write was almost the same aligned vs unaligned.
However, the 512k and 4k random tests brought out the difference. The write speeds were roughly half when misaligned. This was similar to what was observed with the EARS drives.
And to compare the two (EARS vs HD204UI), I would have to say that I think the EARS drives come out on top. Compared to my benchmark on the EARS, the HD204UI had a sequential transfer rate about 10MB/s faster. However, the HD204UI is much slower at the random data. Even when aligned, the 204 was about 20 MB/s slower on 512k writes, and about 10 MB/s slower on reads. The 4k transfer on the EARS drive is about 5% faster vs the HD204UI. Overall, I would say the EARS is a slightly faster drive. For the same money, I would rather have the EARS (strictly from an aligned perspective).
So for unRAID, where sector 63 will be forced, you may be able to use the drive, but it depends...
As a parity drive, no way.
For small files, scratch drive, etc, probably not.
To store large DVD iso's, you could probably get away with it.
It is still something of a mystery to me how preclears could be so fast on the HD204UI unaligned and very slow on an unaligned EARS. One would think both should be equally as slow. But this doesn't appear to be the case.
And I haven't had a chance to play with the Samsung jumpers yet. I doubt they have a jumper like the WD's did, but who knows. I will try it out tomorrow on an unaligned drive to see what happens.